While strumming this 2 week old OM-03 I'm noticing the strings tend to rattle in low
G's and D's while using a medium pick.  I think the cleartone strings are nickel although
not 100% sure.

Does this have something to do with the setup?  Strings? Or when they mean
for 'light' strumming they really mean  'shhh' be quiet there are people trying to read
in here? 

Trying to play David Bowies'  Andy Warhol from Hunky Dory perhaps this OM
is more of a China Girl sounding strum.

I never owned an OM sized guitar before, but I can understand what you are talking about. The action on my L-03 is fairly low. If I strum real hard I get a light fret buzz. I have the action on my Alvarez dread a little higher, therefore I don't get any fret buzz when I pick hard. Generally, I use my L-03 for fingerstyle and light picking. Low action is perfect for it. The Alvarez is more for flat picking and heavy strumming.

It sounds like it's just the action. My OM-03R played that way too and changing strings only partially solved the problem. Looking at the height of the saddle, it looks like it's lower than what I'm used to. The tone could also be clearer so tomorrow I'll be ordering a new bone saddle for it and will probably start off with leaving it on the tall side.

BTW, the OM is an OK strummer but I've come to realize that it's not really meant for that style of playing; it's a better fingerstyle insturment.

paralentor,

You might want to check out the article at Frets.com about truss rod relief.  Not enough relief can get you buzzing in no time.  Low actiion can also cause problems for a heavy strummer.  Take a look at the articles below and you can measure things yourself and get and idea whats going on with your action.

Frets.com Truss Rod adjustments (http://www.frets.com/FRETSPages/Musician/GenSetup/TrussRods/TrussRodAdj/tradj.html)

Buzz diagnosis (http://www.frets.com/FRETSPages/Luthier/Technique/Setup/BuzzDiagnosis/buzzintro.html)

Lower/checking action height (http://www.frets.com/FRETSPages/Musician/Guitar/Setup/LowerAction/loweraction01.html)

I know there are guys here who will happily do their own truss rod adjustments, but I'd just add a word of caution that if you aren't sure about what you're doing, leave it to your friendly neighbourhood repair person.

Sounds to me like a neck relief issue, but if you are concerned see your local repair person.

E. Shoaf

Good input and hopefully this is a minor adjustment.  Might be a truss wrench adjust
issue.  Or needs more breaking in.  I'm here in Florida so the Canadian climate factor
may play in.  I really don't know how long it was at Smash.  Perhaps a change from
the stock Cleartones to the recommended  Phosphor Bronze Nanoweb .012 - .053 (Light)
will make a difference.  Possibly let the guys at the store change them and see how it
plays for them.  I might be able to part with it for a couple of days (gulp) and beat on
my old Martin DM. 

Or, exchange it for a heavier strummer like the D-03, L's were not a choice at Smash.

Had you switched string gauge to medium? Seems strange the rattle is only on the middle strings. It might be a high fret somewhere on the fret board. Take it to a shop and have them look it over.

Andy

If the strings are the same gauge as what you had before that shouldn't matter.

Since it's buzzing in the lower positions the truss rod is the most likely culprit ... it's too bad how often people start messing with the saddle when that's not what you usually should be looking at first.  It's really, really common for the neck to straighten itself out a little in May unless you live in the Southern hemisphere ... the humidity is rising most places and that makes necks back bow a little.  Totally normal.

If you've put on lighter strings, same deal.  Less tension makes the neck straighten as well, which would be the opposite of what you want.  Lighter strings need more relief.

Is your action pretty low?  A downside to low action is that the guitar becomes more sensitive to things like climate variations and uneven frets and needs tweaking more often.  If the only change you've made is string brand it's probably the relief though, not the frets.

It'd be best to take it to a shop probably but you could try loosening the rod a tad.  Tightening it can be troublesome if you don't know what you're doing, catastrophic in fact, but loosening it should be safe.  Only turn it 1/8th of a turn at a time because if you turn it 1/4 turn or more it'll often go past where you want it.  Then let it settle for a couple of days and see if it's still buzzing.